Much ado has been made recently about the importance of sponsors, versus mentors, in the career advancement of women. Just this summer, Catalyst released a study, Sponsoring Women to Success , pointing to the fact that sponsorship may in fact be the single most critical strategy for accelerating a woman’s career.

So just what is the difference between a mentor and sponsor? Think of mentors as the friendly guides who dispense helpful information, offering up input and advice to mentees. Sponsors, on the other hand, are defined by their organizational clout and ability to open doors; they will personally advocate for a cause, project or promotion on a protégé’s behalf.

Women, it’s time to get a sponsor.

What may in effect sound like a slight distinction actually has major implications. Research substantiates that women tend to lag behind men when it comes to promotions, even when women have mentors. Yet when women’s mentors are high ranking—that is to say, when they fall into the ‘sponsor’ category—women are just as likely as men to get promoted. As the Catalyst study authors note, a sponsor “can propel a protégé to the top of a list or pile of candidates or even eliminate the list itself.”

While sponsors have many roles, including protector, advocate and coach, what most people don’t know is that sponsors can have a major impact on how and if we negotiate on our own behalf. A study conducted by economist Sylvia Ann Hewlett explored this aspect. She found, first of all, that both men and women who have sponsors behind them are more likely to ask their managers for a stretch assignment. Without a sponsor, 43 percent of men and 36 percent of women will ask for one; but with sponsor support, the numbers rise, respectively, to 56 percent and 44 percent. Similarly, men and women with sponsors in their corner are more likely to ask for raises than those without.

Given that negotiation conversations, whether about a plum assignment or an increase in pay, are the most materially significant dealings we have on the job, Hewlett’s numbers say a lot. As I’ve written about before, women are already less likely—four times less so—to initiate workplace negotiations than men are, a factor that may be aggravated by women’s tendency to think that meritocracy is king. Hewlett’s survey revealed that a full 77 percent of women think hard work, education and long hours (not relationships or connections) lead to advancement.

As awareness increases about the importance of sponsors, it seems nothing should hold women back from reaching out and engaging these champions. And yet, finding a sponsor isn’t that simple. While it’s commonplace for a protégé to initiate and propel the relationship with a mentor, in sponsorship the dynamic is often reversed. Here, it’s the sponsor that often does the choosing.

And if social psychology tells us anything, it’s that the similarity among two people is a significant factor in encouraging interaction. That can translate to the fact that men, who make up the majority of high-ranking executives, may be more likely to help other men, shutting women out of a high-ranking inner circle without realizing it. What’s more, professional women can easily find themselves in a “husband/wife” or even “father/daughter” dynamic with older male colleagues.

Hewlett goes so far as to say, “Sponsorship, which often involves an older, married male spending one-on-one time, often offsite and after hours, with a younger, unmarried female, can look like an affair; and the greater the power disparity between the male and the female, the more intense the speculation becomes that the relationship is more than professional….In short, because sponsorship can be construed as sexual interest, highly qualified women and highly placed men avoid it.”

Companies that understand this bind are doing something to make the sponsor-protégé relationship open, clear and transparent. They also imbed into the culture the expectation that those who want to be leaders must develop and advocate for junior workers—some even tie performance reviews and bonuses to executives’ track records as champions.

Whether at an organization that explicitly awards such behavior or not, sponsors often don’t engage for charity alone. Hewlett found that while the No. 1 benefit sponsors cited was “Satisfaction in paying it forward,” “Gains for me when protégé goes the extra mile” and “Looking good when protégé is successful” were also important.

Yes, getting a sponsor means strategically engaging another person. But at its core, it’s really the ultimate form of self promotion. Success hinges on women’s willingness to regularly vocalize their accomplishments to key higher-ups. Sponsors want to be ‘sold’ on the performance and potential of a protégé, and it’s hard to make the ‘sale’ if you’re wed to modesty. If sponsorship is ultimately about making sure women are backed and endorsed completely, the first order of business is to back and endorse ourselves.

Selena Rezvani is the author of The Next Generation of Women Leaders: What You Need to Lead but Won't Learn in Business School and co-president of Women's Roadmap.

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